January 28, 2012

This artist's concept shows an overhead view of the orbital position of the planets in systems with multiple transiting planets discovered by NASA's Kepler mission, and announced on Jan. 26, 2012. All the colored planets have been verified. The planet candidates shown in grey have not yet been verified.

NASA’s prolific planet-hunting spacecraft has hit the jackpot again, discovering 11 new planetary systems with 26 confirmed alien planets among them.
The findings nearly double the number of bona fide planets found outside our solar system by the Kepler space observatory.
“Prior to the Kepler mission, we knew of perhaps 500 exoplanets across the whole sky,” Doug Hudgins, Kepler program scientist at NASA headquarters in Washington, said in a statement. “Now, in just two years staring at a patch of sky not much bigger than your fist, Kepler has discovered more than 60 planets and more than 2,300 planet candidates. This tells us that our galaxy is positively loaded with planets of all sizes and orbits.”

The newly detected worlds vary in size from 1.5 times the radius of Earth to larger than Jupiter; 15 of the 26 planets fall between Earth and Neptune in size. While all of the planets tightly orbit their parent stars, more research will be required to determine which worlds are rocky like Earth, and which have thick, gaseous atmospheres like Neptune, the scientists said.

Still, all of the 26 new planets orbit closer to their stars than Venus does to our sun. This means that their orbital periods — or the time it takes for them to complete one orbital lap around the star — range from six days to 143 days, according to the researchers. [Gallery: A World of Kepler Planets ]

The Kepler spacecraft, which orbits the sun, stares at a patch of sky that contains 150,000 stars and locates potential alien planets by measuring the tiny change in brightness that occurs when a planet transits — that is, passes in front of — a star.

Once a planetary candidate is identified, further observations are conducted by ground-based observatories to weed out the false positives.

“Confirming that the small decrease in the star’s brightness is due to a planet requires additional observations and time-consuming analysis,” Eric Ford, associate professor of astronomy at the University of Florida, explained in a statement.

Ford is the lead author of a study that confirms two of the new systems, Kepler-23 and Kepler-24.

“We verified these planets using new techniques that dramatically accelerated their discovery,” Ford said.

Each of the newly found planetary systems holds two to five closely spaced transiting planets, the researchers said. Since these systems are tightly packed, the planets exert gravitational forces on one another, speeding up or slowing down their orbits. The orbital period of each planet is altered in the process.

By measuring the orbital changes, Kepler can identify potential planets in the system. This method, known as Transit Timing Variation, can be used to verify alien planets without extensive ground-based observations. The technique also increases Kepler’s ability to confirm planetary systems around fainter and more distant stars, the researchers said. [Video: Kepler Reveals Lots of Planets: Some Habitable?]

“By precisely timing when each planet transits its star, Kepler detected the gravitational tug of the planets on each other, clinching the case for 10 of the newly announced planetary systems,” Dan Fabrycky, of the University of California, Santa Cruz, said in a statement.

Fabrycky is the lead author of the paper that confirms the Kepler-29, -30, -31 and -32 systems.

Alien planets and their host stars

Five of the systems (Kepler-25, -27, -30, -31 and -33) contain a pair of planets, the inner one circling its star twice in the time it takes the outer planet to make one lap.

Four of the systems (Kepler-23, -24, -28 and -32) are home to a pair of planets where the outer one orbits the star twice for every three times the inner planet circles the parent star.

“These configurations help to amplify the gravitational interactions between the planets, similar to how my sons kick their legs on a swing at the right time to go higher,” Jason Steffen, a postdoctoral fellow at Fermilab Center for Particle Astrophysics in Batavia, Ill., said in a statement. Steffen is the lead author of a paper confirming the Kepler-25, -26, -27 and -28 systems.

The system with the most planets is Kepler-33. The star, which is older and more massive than the sun, hosts five planets that range in size from 1.5 to five times that of Earth. All of these planets orbit closer to their star than any planet circles our sun.

Once the properties of a star are understood, such as the telltale light signature of a planet crossing in front, it becomes easier to eliminate false positives, the researchers said.

“The approach used to verify the Kepler-33 planets shows the overall reliability is quite high,” said Jack Lissauer, planetary scientist at NASA Ames Research Center at Moffett Field, Calif., and lead author of the paper on Kepler-33. “This is a validation by multiplicity.”

January 27, 2012

From “wow, that’s cold” we now get to meet a “wow, that’s hot” laser application, courtesy of the US Department of Energy’s SLAC National Accelerator Laboratory: its X-ray laser has created and probed matter as hot as the Sun’s corona.

In a busy day at SLAC, the lab announced the creation of 2-million-degree Celsius matter, and also fired the LCLS at neon atoms to create the first “Atomic X-Ray laser”.

One announcement covered the creation of a new kind of laser – the Atomic X-Ray Laser. By firing SLAC’s Linac Coherent Light Source at a capsule of neon gas, the scientists got the neon to emit coherent X-rays.

It works like this: the LCLS’s X-ray pulses knocked electrons out of the inner shells of neon atoms in the target, and when electrons dropped down into the vacated lower-energy orbits, they shed photons. However, instead of the visible light laser we’re familiar with – and which also works by inducing electrons to shed photons as they shed energy – the SLAC technique generated high-energy photons in the X-ray range.

The laser X-rays generated by the neon atoms are, the group says, more pure and have one-eighth the wavelength of the laser fired by the LCLS, making it suitable for capturing reactions much faster than have been observed before.

The atomic laser also fulfills a prediction from the earliest days of lasers, that coherent X-rays could be generated by the same phenomena that produces visible coherent light.

The Linac 2M°C chamber. Photo: Sam Vinko and Oxford University

The other SLAC LCLS experiment, announced at the same time, was to fire the instrument at a tiny piece of aluminium foil. The result was a ten-micron cube of a special plasma known as “hot dense matter”.

Very hot, in fact: in the vicinity of 2 million degrees Celsius, similar to the temperature of the Sun’s corona. The LCLS was used to take the temperature of the plasma in the tiny instant – less than a picosecond – for which it existed.

Sam Vincko, a postdoctoral researcher at Oxford University and lead author of the paper demonstrating the hot dense plasma, says the creation of this matter “is important … if we are ultimately to understand the conditions that exist inside stars and at the centre of giant planets within our own solar system and beyond”.

And that was just using LCLS: The Register presumes that once SLAC is able to operate its X-Ray Atomic laser on a routine basis, even higher temperatures will be feasible.

Participants in the plasma research were led by Oxford University, and included scientists from SLAC, Lawrence Berkeley and Lawrence Livermore national laboratories, and five international institutions. The Atomic X-Ray laser was all SLAC’s own work.

Image of Earth from the Suomi NPP(NASA/NOAA/GSFC/Suomi NPP/VIIRS/Norman Kuring)

The newly renamed Suomi NPP satellite has snapped a hi-res composite of the Earth from a number of swaths over the surface taken on 4 January.

The National Polar-orbiting Operational Environmental Satellite System Preparatory Project, or NPP, was launched at the end of October last year. It was recently renamed the Suomi NPP in honour of the late Verner E Suomi, known as the father of satellite meteorology.

The mission is a bridge between NASA’s Earth Observing System satellites to the next-generation Joint Polar Satellite System, or JPSS, a National Oceanic and Atmospheric Administration (NOAA) programme.

Suomi, who was a meteorologist at the Univerity of Wisconsin, pioneered remote sensing of Earth from satellites in polar orbits a few hundred miles above the surface with Explorer 7 in 1959, and geostationary orbits of thousands of miles with ATS-1 in 1966.

He was also the inventor of the “spin-scan” camera, which allowed geostationary weather satellites to continuously capture snapshots, giving us the pictures commonly used on TV weather forecasts.

“It is fitting that such an important and innovative partnership pays tribute to a pioneer like Verner Suomi,” said Mary Kicza, assistant administrator for NOAA’s Satellite and Information Service.

“Suomi NPP is an extremely important mission for NOAA. Its advanced instruments will improve our weather forecasts and understanding of the climate and pave the way for JPSS, our next generation of weather satellites.”

January 19, 2012

A conference being held this week in Arizona will lay the groundwork for an attempt to visualize the supermassive black hole that resides at the heart of our galaxy.

Since a black hole absorbs light itself, the Event Horizon Telescope (EHT) team is looking for the ring of matter that forms around the perimeter of the structure. If Einstein’s equations behind the General Theory of Relativity are correct, the matter around the edge of the event horizon will form a circle as it spins around the rim.

“Black holes are like babies, they are very messy eaters,” Sheperd Doeleman, principal investigator of the EHT, told The Register. “A lot of what a black hole tries to eat ends up sprayed across the galaxy.”

The EHT program will plan how to coordinate 50 radio telescopes across our planet to focus on the black hole center of our galaxy. This galactic maw has around four million times the mass of our sun and is 26,000 light years away – about 245,979,000,000,000,000 kilometers, give or take a few trillion. Trying to image this from earth is the equivalent looking for a grapefruit on the surface of the moon – catching an image of the black hole’s surroundings will take a telescope over 2,000 times as powerful as Hubble, according to Doeleman.

There are many black holes in our galaxy, but almost all are relatively small and thus hard to spot. It is thought that they originated as stars that went supernova, but the hole at the galactic center is a different kettle of fish, thought to have grown concurrently with the galaxy, and is big enough to be visible.

“We’re hunting big game, we need a large target to see,” Doeleman explained. “The galactic center is the Goldilocks black hole, just at the right distance and mass to resolve the event horizon.”

The team has already conducted a preliminary scan, using three networked radio telescopes, which have determined that there is an object in the target zone. Now many more telescopes are needed to capture the first images of the center of the Milky Way – a project that could be completed in the next three or four years, now that the team has proven that it’s technically possible and that there is an object to study.

January 13, 2012

Lately, all of the absolute land speed record talk that we’ve been reading about is in relation to the Bloodhound SSC, a beast of a jet/rocket-engined streamliner with visions of 1,200 mph.

Right now, though, the record stands at 763 mph, leaving several milestones before Bloodhound’s ambitious 1,200-mph goal.

Well, 800 mph is officially in the sights of one man with a whole lot of land speed record credentials. Craig Breedlove was the first to break the 400-mph barrier back in 1963, when he powered the Spirit of America to 408 mph.

Breedlove’s record came at the start of a sort of land speed-record renaissance, and he spent the next two years swapping places with several other teams, eventually breaking the 600-mph barrier in 1965.

While the record has risen over 150 mph since that period, it’s remained at 763 mph since Thrust SSC clocked it back in 1997. Breedlove and his team of engineers attempted to set a record that same year with a redesigned ‘Spirit’, but never made the books due to engine damage.

But Breedlove isn’t done yet. He has some big plans for the 50th anniversary of his first land speed record and will make an attempt at doubling the accomplishment by becoming the first to break 800 mph. Breedlove won’t actually be driving himself but will be part of the engineering team that develops the jet-powered streamliner to do the job.

According to Hemmings, Breedlove and company plan to attempt the record in 2013 at Utah’s Bonneville Salt Flats, where Breedlove set his records in the 1960s.

If you look at the history of the absolute land speed record, it’s a story of intensified efforts during several key periods and subsequent inactivity for years and decades. Breedlove’s 1963 record ended a 16-year drought and was the first of 11 records set over the course of two years. The 1970s, ’80s and ’90s saw one record per decade and there have been none since.

But it looks like we could be on the brink of another renaissance. In addition to Breedlove’s team and the Bloodhound SSC team, several other teams around the world are working on streamliners to take on the speed record. So we could very well see a multitude of world records over the next few years.

January 9, 2012

By analyzing the light from 10 million galaxies, astronomers have built the largest dark matter map ever created.

Astronomers have created a vast cosmic map revealing an intricate web of dark matter and galaxies spanning a distance of one billion light-years.
This unprecedented task was achieved not by observing dark matter directly, but by observing its gravitational effects on ancient light traveling from galaxies that existed when the Universe was half the age it is now.

Constructed by astronomers from the University of British Columbia and University of Edinburgh, this is the largest dark matter map ever built and took five years to complete.

The research was presented at the American Astronomical Society meeting in Austin, Texas, on Monday.

Dark matter pervades the entire observable universe, accounting for 83 percent of the mass of the cosmos. But as it does not scatter or radiate light (or any kind of electromagnetic radiation for that matter), we cannot see it. Naturally, this poses an interesting problem for astronomers hoping to map the stuff.

However, astronomers can indirectly observe dark matter as its mass exerts a gravitational force on the space-time surrounding it. As light travels from distant galaxies, it will be bent around gravitational distortions in space-time — much like the paths of marbles rolling across a bent sheet of plastic — being caused by the dense regions of dark matter.

With this in mind, the international team of astronomers analyzed light from 10 million galaxies in four different regions of the sky — all of which are around 6 billion light-years from Earth. As these galaxies are six billion light-years away, it took the light six billion years to travel that distance.

Using a 340 Megapixel camera called “MegaCam” attached to the Canada-France-Hawaii Telescope (CFHT) in Hawaii, the ancient galactic light was analyzed to reveal the distorted paths each source traveled thereby revealing the gravitational terrain surrounding clouds of dark matter.

“It is fascinating to be able to ‘see’ the dark matter using space-time distortion,” said Ludovic Van Waerbeke from the University of British Columbia.

“It gives us privileged access to this mysterious mass in the Universe which cannot be observed otherwise.”

Catherine Heymans, from the University of Edinburgh’s School of Physics and Astronomy, added: “By analyzing light from the distant Universe, we can learn about what it has traveled through on its journey to reach us. We hope that by mapping more dark matter than has been studied before, we are a step closer to understanding this material and its relationship with the galaxies in our Universe.”

Both Heymans and Van Waerbeke lead the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) team.

It is now hoped that other observatories — such as the Very Large Telescope’s (VLT) Survey Telescope in Chile — will build on the CFHTLenS feat and create an even bigger dark matter map.

“Over the next three years we will image more than 10 times the area mapped by CFHTLenS, bringing us ever closer to our goal of understanding the mysterious dark side of the Universe,” said Koen Kuijken of Leiden University.

Understanding the nature of dark matter is critical to our knowledge of how the Universe evolved to form planets, stars and galaxies. Mapping this vast — yet invisible — cosmic web is a big step in that direction.Source

Near-infrared (1.6 micron) image of the debris ring around star HR 4796 A. An astronomical unit (AU) is a unit of length that corresponds to the average distance between the Earth and Sun, almost 92 million miles (149 million km). (NAOJ)

The Strategic Exploration of Exoplanets and Disks with Subaru Telescope/HiCIAO (SEEDS) project, a five-year international collaboration launched in 2009 and led by Motohide Tamura from the National Astronomical Observatory of Japan (NAOJ) has yielded another impressive image that contributes to our understanding of the link between disks and planet formation. Researchers used Subaru’s planet-finder camera, High Contrast Instrument for the Subaru Next Generation Adaptive Optics (HiCIAO), to take a crisp high-contrast image of the dust ring around HR 4796 A, a young 8- to 10-million-year-old star that is only 240 light-years from Earth. The ring consists of dust grains in a wide orbit, roughly twice the size of Pluto’s orbit, around the central star. The resolution of the image of the inner edge of the ring is so precise that an offset between its center and the star’s position can be measured. Although data from the Hubble Space Telescope led another research group to suspect such an offset, the Subaru data not only confirm its presence, but also reveal it to be larger than previously assumed.

What caused the wheel of dust around HR 4796 A to run off its axis? The most plausible explanation is that the gravitational force of one or more planets orbiting in the gap within the ring must be tugging at the dust grains, thus unbalancing their course around the star in predictable ways. Computer simulations have already shown that such gravitational tides can shape a dust ring into eccentricity, and findings from another — the eccentric dust ring around the star Fomalhaut — may be observational evidence for the process. Since no planet candidates have been spotted near HR 4796 A yet, the planets causing the dust ring to wobble are probably simply too faint to detect with current instruments. Nevertheless, the Subaru image allows scientists to infer their presence from their influence on the circumstellar dust.

The Subaru Telescope’s near-infrared image is as sharp as the Hubble Space Telescope’s visible-light image, thus enabling accurate measurements of its eccentricity. While the Subaru Telescope’s mirror is much larger than Hubble’s, light from the HR 4796 A system must first pass through the turbulent layers of Earth’s atmosphere before Subaru’s instruments can measure it. Subaru’s adaptive optics system allows it to correct for most of the atmosphere’s blurring effects in order to take razor-sharp images. The application of an advanced image processing technique, angular differential imaging, to the data suppressed the star’s bright glare and enhanced the faint light reflected from the ring so that it was more visible.

This image gives scientists more information about the relationship between a circumstellar disk and planet formation. Planets are believed to form in the disks of gas and dust that remain around young stars as the byproducts of star formation. As the material is swept up by the newborn planets or blown out of the system by the star’s radiation, such primordial disks soon disappear in a few tens of million years. Nevertheless, some stars are surrounded by debris or a secondary disk, which is mainly composed of dust long after the primordial disk should have dispersed. Collisions between small solid bodies — planetesimals — left over from planet formation may continuously replenish the dust in these disks. The dust ring around HR 4796 A is such a debris disk and provides essential information for studying planet formation and possible formed planets in such debris disk systems.